Testing device for internal combustion engines



June 2Q, 1933. '.J. J. FERNANDEZ TESTING DEVICE FOR INTERNAL COMBUSTION ENGINES l Filed Jan. 23. 1951 @hij 60% 2 Sheets-Sheet 1 A HHN/IHMAINHAIHHNAVIYIINIIIIIINAINHNA/n K MY 564450/050/050/050/0 gqm =lu pim qu q E@ i:

Hilary/v June 20, 1933. J. J. FERNANDEZ 1,914,496

TESTING' DEVICE FOR INTERNAL COMBUSTION ENGINES Filed Jan. 23, 1951 2 sheets-sheet 2 Patented l,lune 20, 1933 UNITED ,STATES PATENT OFFICE JOHN J. FERNANDEZ, OF BALTIMORE, MARYLAND, ASSIGNOR OF ONE-FOURTH TO MORGAN S. GIBSON, OF BALTIMORE, MARYLAND V TESTING DEVICE FOR INTER-NAL COMBUSTION ENGINES Application led January 23, 1931. Serial No. 510,806.

The invention relates to a method of and apparatus for testing internal combustion engines for the purpose of indicating and loeating defects in operation and in operative parts, Without disconnecting circuit wires, spark plugs or other accessories and while the engine is running under usual conditions of operation. as will be particularly pointed out in the following specification and as illustrated in the accompanying drawings, in which:

F ig.` 1 isa plan view of the device employed in carrying out the method, the lid or closur of the box beingremoved.

. Fig. 2is a front sectional elevation.

Fig. 3 is a section on line 3 3 of Fig. 2.

Fig. 4 isa fragmentary section on line 4 4 of Figi 2.

Fig. 5 is a conventional diagram of the apparatus connected to a multi-cylinder internal combustion engine.

Fig. 6 is a plan view of a special type of indicator with the top removed. 'l

Fig. 7 is a section on line 7--7 of Fig. 6.

The common defects and troubles devel-4 oped by internal combustion engines and their accessories, such as defective spark coils, impaired distributors or timers, improper carbureter action, and various derangements or impairments of the engine parts evidenced bv noises or knocks, generally designated as piston slap, connecting rod, main bearing and wrist pin knocks, leaking piston rings resulting in insuflicient or weak compression, ignition troubles at high and low speed, sticking valves, defective cylinder head gaskets, and defective spark plugs, including broken or impaired plugs, or plugs with too large or toosmall spark gaps, usually require the stopping of the engine and a careful overhauling of the variousparts of the engine y-and its accessories, in order to locate the particular trouble.

The present invention involves a method of testing mult'icylinder internal combustion engines under normal condition of operation, without disconnecting any of theparts, that will indicate and enable the operator or repairman to locate the particular trouble or defect quickly and certainly, so that the necessary repairs or adjustments may be made with a minimum expendlture of time and labor, the method mvolvmg short circuiting the ignition means of the several cylinders successively to develop audible evidence of defective operation in any cylinder or cylinders, then suspending the ignition in all of the cylinders except that involving defective operation, so that the engine will be operated from the single cylinder with which the defect is associated and the lcharacter and location of the defect or trouble will be indicated either by the sound produced or by the peculiarities of operation of the single cylinder. The apparatus developed for applying the method also involves additional means for testing and locating structural or operative defects in the various accessories of the internal combustion engine, such as the carbureter, the timer or distributor, the spark' coil, and condenser, as will be more particularly pomted outl in the detailed description thereof.

Referring to the drawings, which are illustratlveof arelatively simple but purely exemplary form of the apparatus, 1 indicates a box or casing, preferably made of insulatlng material and provided with a removable slide cover, not shown, the said box or casing being designed to house the entire apparatus when the latter is not in use and to permit it to be readily transported to and.

set up at the place. of use. Removably mounted within the box is a framework, preferably made of insulating material, which includes a panel or top section 2, which fits snugly within the box in the manner and.

form particularly illustrated in Figs. 1, 2 and 3, the framework also including a housing section 7 provided with end walls 7', 7 and an intermediate partition 7". The panel 2 is provided with a longitudinal rectangular opening 6, which is closed by a transparent medium, such as a strip of glass 3, and two series of sight openings 5 and 5 respectively, each series in the apparatus shown including eight openings, sothat the apparatus is adapted to testing engines having four, six or eight cylinders. rlhe series of openings indicated bythe reference numeral 5 is located adjacent to and parallel with the rectangular opening 6 and the other series indicated by the reference numeral 5 is disposed toward the opposite edge of the panel. Below the opening 6 is a shelf 4 upon` which is mounted or applied a series of scales 0r indices graduated to show spark gaps in thousandths of an inch, as employed in engines of various types, the said indices bearing the markings HC, STD and LC, indicating high compression, standard compression and low compression, the normal gap for high compression being twenty thousandths, that for standard twenty-five thousandths, and for low compression thirty thousandths of an inch, which distances are also shown on the graduated scales.

Mounted in suitably threaded bushings carried by the panel 2 and in alignment with the sight openings 5 is a series of normally fixed but adjustable spark gap terminals, each comprising a screw threaded spindle 11, which engages the threaded thimble mounted in the panel and is provided with an operating knob or handle 10. Fixed to each spindle 11 is a pointer 12, which c0- operates with the scales or indicia 12 -on the shelf 4. By adjusting the screw spindles 11, the extreme points of the same may be raised or loweredto determine the width of the gap between said ends and certain movable gap terminals to be hereinafter explained, the pointers on the spindles indicating the width of the gap in thousandths of an inch, by direct reference to the indicia, as described.

Mounted longitudinally of the housing 7 and immediately below the ends of the screw spindles 11, constituting the adjustable fixed spark terminals, is a shaft 14, preferably made of insulating material, one end of which is journaled in an end 7 of the housing and the other end in the intermediate partition 7". This shaft is adapted to be rot-ated at a relatively slow rate of speed as compared with that of the internal combustion engine to be tested by means of the train of reducing gears indicated at 19, interposed between the shaft and an electric motor 18, which is mounted in the housing. Fixed to the shaft 14 is a series of cams'or cam-shaped lugs 15, which are adapted to be rotated past the ends of the corresponding fixed terminals 11, so that, when the arcuate edge of the high part of any cam comes opposite the corresponding fixed terminal, a spark or a series of sparks will pass the gap between the cam and the fixed terminal, if the circuit conditions are proper and when the apparatus is adjusted to this end, as will be hereinafter explained, and any spark that passes will be refiected by a mirror 9, fixed at an angle of 450 to the plane of the panel, through the corresponding sight opening 5 and may be observed by the operator. The relation of the high part or arcuate section 0f each caIIl to the point of the corresponding spindle 11 is such that the distance between the point of the spindle and the cam may be accurately regulated by adjusting the screw spindle, the distance being indicated by the pointer 12 carried by the spindle and the markings on the scale 12. l

Each of the cams or movable spark gap terminals 15`is engagedat all times by a corresponding spring contact 16, which is fixed to the vertical wall of the housing 7 by a terminal screw or connector passing through the wall and having attached thereto a conductor lead 20, including a relatively high resistance and which may take the form of a wick coated or saturated with an admixture of .powdered brass, powdered aluminum and Varnish, the other end of said conductor 20'being connected to the terminal contact 21 of a double throw rotary switch, including a knobbed spindle 23 journaled in the panel 2, with a knife blade attached to the end thereof, said blade being adapted to be rotated by the spindle to engage said fixed contact 21 'or a second fixed contact 25, said contacts being secured to the under .side of the panel 2.

Electrically connected to each contact 21 and the spindle or movable member of the corresponding switch are two spaced sparking terminals 28 and 27, respectively, constituting a fixed spark gap lying immediately below the corresponding sight opening 5', the several fixed spark gaps thus constituted therefore being interposed between the leads 30 to the respective spark plugs of the engine and the ground, so that, if any of the engine spark plugs are damaged or deranged sufiiciently to prevent the passage of sparks between the terminals thereof, the sparks will jump the space between the corresponding fixed terminals 27 and 28 and will afford immediate evidence of the defective plug or plugs.

Connected to each of the fixed terminals 21 of the several rotary switches are insulated wires 30, fitted at their ends with clip connectors 31 to enable the conductors 30 to be quickly attached to or detached from the spark plug terminals or the ignition leads connected to said terminals, the clips preferably being protected by soft rubber sleeves slipped over the same, as indicated in Fig. 3. The several conductors or leads 30 pass through openings in the panel 2, as indicated in Figs. 1 and 3, and, when not in use, may be coiled up and disposed within the box on top of the upper panel. The other fixed contact 25 of each of the rotary switches is electrically connected by a lead 26 to the screw spindle 11 of the corresponding fixed spark gap'terminal. The shafts or spindles 23 of the rotary switches are connected to a common ground lead 34, which lead is provided at its end with a spring clip adapted llO Vdesired degree with a corresponding variation of the speed of the shaft 14, so that the apparatus is adapted to test engines operating from the highest to the lowest normal speeds. The circuit to the motor is made and broken at the rheostat by the movable arm For the purpose of testing the distributor and the general ignition conditions, as evidenced by the operations of the spark plugs ofthe engine, there is provided an additional test circuit including a lead adapted to be connected by a clip or similar means to the lead to the distributorI D, in which lead there is interpolated a rheostat including 'a resistance 52, which is adapted to be included in Whole or in part or wholly excluded from the circuit by means of Ythe rotary contact arm 51, which cooperates with fixed contacts connected to various points of the resistance, as diagrammatically illustrated in Fig. 5. Beyond the rheostat, the circuit includes lead 53, in 4which is interposed a lamp or other signalling device, such as 54, visible through an opening 54 in the panel 2, the lead 53 terminating in a multiple switch 56,

which, in turn, is connected with'the common ground 34. The lead 50 is branched at. 57 in which is interpolated a special form of indicator 58, which in its general construction resembles Ia volt meter and is adapted to indicate the relative speed of operation of the distributor by means of the hand or pointer operating over the dial face of the instrument, and also is adapted to indicate defective operation of the carburetor bv a vibration ofthe hand. The other terminal of the indicator 58 is connected by lead 59 with the multiple switch 56, which, as indicated, is adapted to connect either the rlieostat and the light signal 54 between the distributor and the ground, or said indicator 58 between the distributor and the ground.

The apparatus includes an additional test circuit for testing the condition of the spark 16, said brush 61 adapted to be engaged successively by the arms of a star-shaped conductor member 62 mounted on the shaft 14, as illustrated .in Fig. 4, the arms of the member 62 constituting movable terminals of a sparking device, the other member of which comprises an arm 63 connected to the end of a spindle 64 mounted on the panel 2 and having a knob or finger piece 64 by means of which the spindle is rotated and the arm 63 adjusted toward and from the path of movement of the arms of the member 62. The arm 63 is connected by a lead 65 with a fixed terminal G6 of a switch 67 comprising a spindle mounted on panel 2 and provided with an operating knob 68, the movable member of the switch being connected to the ground 34. The spark gap established between the arms of the member 62 mounted on shaft 14 and the arms 63. of the adjustable lierminal is visible through a sight opening 69 in the panel. This test circuit is adapted for indicating .the character ofthe spark developed by the coil and condenser for various spark gap adjustments and the circuit is completed, when it is desired to make a test, by turning the knob 68 to engage the blade 67 of the rotary switch with the fixed Contact 66. Then, by adjusting the arm 63 of the sparking device toward and from the path of movement of the rotary member 62, the character of the spark developed may be observed through the sight opening 69.

As hereinbefore stated, the appara-tus is adapted to be connected to the engine of an automobile without disconnecting any of the operating elements of the power plant of the machine and, by systematic operation of the various elements of the apparatus, practically all of the-structural and operative defects of the engine and its accessories may be detected, located and diagnosed without interrupting the normal operation of the engine, so that the defects of whatever nature may be corrected at a minimum expenditure of time and labor. In applying the device to its intended use, the several leads 30 are connected to the corresponding spark plug terminals or leads of the internal combustion engine, the lead 34 is connectedl to the engine framework or the chassis ofthe machine to esablish Ia common ground, lead 40 is connected to the positive terminal of the automobile battery, lead 50 is clipped to the main lead of distributor D and lead 60 connected to the lead from the spark coil C. As these connections are preferably made by means of the ordinary spring clips attached to the ends of the leads or cables, it will be apparent that the necessary con nections can be quickly made without disturbing any of the operating parts of the internal combustion motor or its accessories. In operating the device to test the ignition, as affected by the spark plugs of the respective cylinders, the several switches 23 CTI are adjusted to engage contacts and motor 18 is started at high, low or any intermediate speed, depending upon the type of internal combustion engine with respect to the normal operating speed thereof. The operation of the motor drives the shaft 14 at a much slower rate of speed than that of the engine and brings the movable spark gap contacts 15 successively opposite the corresponding fixed contacts 11, which latter have been adjusted by means of the knobs 10 thereof for high compression, standard compression, or low compression, according to the type of engine. The spark gaps between the respective terminals 11 and 15 are, therefore, in parallel with the spark plugs of the corresponding engine cylinders, so t'hat the character of the, spark passing between the terminals of the spark plugs will be duplicated at the corresponding terminals 11 and 15 of the'testing device, and ima-ges of the sparks so developed will be defiected by the mirror 9 through the sight openings 5. If the sparks developed at the several spark plugs o'f the engine are of a proper and uniform intensity, they will be' evidenced by uniform fiashes refiected from the mirror through the several peep holes or sight openings, as described.

Should any one of the reflected spark ima ges indicate any departure from normal, there is immediately afforded evidence of either a defective plug or defective connection in the ignition circuit to the plug. If the trouble is not in the plug, it should be looked for in the distributor and, when located, may be readily corrected. The test for ignition defects, as indicated, is carried out with each of the cylinders `in order.A The proper spacing of the spark plug `terminals can be determined by adj ustine'` the screw spindles 11 of the fixed contacts toward and from the movable contacts 15 carried by the shaft 14, and, if any of said spark terminals are improperly spaced, this defect will be manifested by the character of the' spark passing between the corresponding fixed and movable terminals of the instrument. Likewise, by adjusting the screw spindles toward and from the` movable contacts 15, the exact spacing of the spark plug terminals of each cylinder may be accurately measured, as this distance will be indicated in thousandths of an inch on the dials 12 by the pointers 12.

Should the engine develop unusual noises or knocks, the same may be Areadily located by successively short circuiting the ignition circuits of the several spark plugs, thereby suspending the operation ofthe several cylinders successively until the particular cylinder in which the trouble may be located is found` which will either be evidenced by the cessation of the`noise or the intensification thereof. This short circuiting is effected by moving the contact arms 24 of the rotary switchesy successively into engagement with the fixed contacts 21, which connects the spark plugs of the engine directly to ground by way of leads 30. In order to insure the selection of the cylinder in connection with which the defect occurs, the ignition circuits to all of the other cylinders are short circuited by the switches 23 as aforesaid, lso that the engine will be operated by the single cylinder in which the defect is developed and will evidence the defect and the nature thereof by the character of the noise or sound developed, which sounds are usually typical and are readily recognized by a mechanic familiar with the operation of internal combustion engines, such, for example, as a piston slap, a connection rod knock, a main bearing knock, a wrist pin knock, weak compression, a sticky valve, or a blown cylinder head gasket. If other defects are present, as

evidenced by the persistence of any of the,

characteristic noises, all of the other cylinders are similarly tested and the defects located.

It is also to be noted that the adjustability of the fixedv terminals l1 of the spark gaps of the instrument enables the operator to show the amount of compression under which the Several plugs will fire properly in different types of engines. When the testing device is to be used for testing an engine of high compression type, the several fixed terminals 1l are adjusted by turning their knobs until their pointers register with the index HC and the test is carried out as before described. lVhen making this test, the motor 18 is speeded up by cutting down the resistance 42 in the motor circuit by shifting the switch arm 44 of the rheostat. This will cause the shaft 14 carrying the movable spark plug contacts to be rotated at a higher rate of speed. Similarly 1n testing a motor of standard compression, the fixed contacts are adjusted to to position LC and the several operations,

as hereinbefore described, performed to test the several cylinders for defects either o f mechanism or of operation.

By moving the switch 56 to close the circuit to the distributor by way of lead 50, the rheostat and signal lamp 54 and then successively adjusting the movable member 5l of the rheostat to its several positions, the ignition system may be tested to establish the efiiciency of the same, as indicated on the segmental chart associated with the pointer on the knob of the movable member 51 of the rheostat and by the operation of the red light 54 viewed through the sight opening 5. When the rheostat is adjusted to the position marked 1 or 2 and the motor cuts out or stops, it is evident that the distributor points need attention and should be cleaned, filed and adjusted, if necessary. If the points are too close,'the red light 6 will go out and if the cuit of a corresponding engine cylinder, a l

points are too open, this fact will e evidenced by flickering of the light. When the rheostat is adjusted to point 3 on the scale and the condenser is weak, the motor will stop. When the rheostat member is moved from points 4 to 8, inclusive, to cut in the successive elements of the rheostat 53, the general efficiency of the sparking system will be evidenced by the degree of illumination of the`Y light 54, the indications showing the efiicien'cy of the sparking system in terms of percentages.

By shifting switch 56 to the position shown in Figs. 1 vand 5, the indicating instrument 58 is included in the circuit formed by lead from the distributor and the relative speed of the engine will be evidenced by the position shown by the hand of the indicator on the scale, which is regulated by the rapidity of the make and break occurring at. the distributor. If the hand of the indicator stands steadily in a given position, it indicates that the system is working properly, but, if the hand vibrates or sets up a trembling motion, this is evidence of faulty carbureter action or adjustment, which can be readily corrected once the indication thereof is made.

The final test circuit is that involving the lead 60 from the coil C and its associated condenser, which lead 60 is adapted to be successively connected to the ground through the spark gap formed by the rotating terminal 62 mounted on the shaft 14 and the adjustable blade 63, which latter is vcontrolled by the knob 64', as hereinbefore explained. The ef- .fficiency of the coil and the condenser will be evidenced by the character of the sparks developed between the arms of the member 62 and the blade 63y and, as the latter is adl j ust-able toward and from the path of movement of the arms 62, the fairly rapidly recurring sparks'at the gap, when the circuit is closed by the switch arm 67, will afford a ready index of the operation and condition of the coil and the condenser.

F rom the foregoing description, it will be evident that the apparatus, when properly .used by an operator familiar with the diagnosis of engine troubles, generally, will quickly and accurately indicate and locate any of the several troubles hereinbefore stated, without disconnecting any of the operating parts of the engine or its accessories and While the latter is operating under normal working conditions.

What I claim is:

1. A testing device for internal combustion engines, comprising a series of spark gaps each including a fixed terminal and a movable terminal, a rotary shaft. upon which the movable terminals are mounted to move past the corresponding fixed terminals, a separate lead from one terminal of each gap adapted to be connected to the spark plug cirground lead, and a. switch for each spark gap adapted to connect each to the ground lead or to connect the corresponding spark plug lead to the ground.

2. A'testing device for internal combustion engines, comprising a series of spark gaps each including a fixed terminal and a movable terminal, a rotary shaft upon which the movable terminals are mounted for periodic movement past the fixed terminals, and an electric motor for drivingthe shaft, a separate lead from oneV terminal of each gap adapted to be connected to the-spark plug circuit of a corresponding engine cylinder, a ground lead, and a two-way switch for each spark gap connected to the ground lead and adapted to connect one or the other terminal of the corresponding gap to ground.

. 3. A testing device for internal combustion engines, comprising a series of spark gaps each including an adjustable fixed contact and a movablecontact, a motor driven shaft upon which the movable contacts are mounted to move past the corresponding fixed contacts, a separate lead from one contact of each gap adapted to be connected to the spark plug circuit of a corresponding engine cylinderfa ground lead, and a switch for each spark gap adapted to connecteach to the ground lead or to connect the corresponding spark plug lead to the ground.

4. A testing device for internal combustion engines, comprising acasing, an insulating frame therein including a panel having a transparent section and a series of sight openings therein, a mirror supported in angular relation' adjacent said sight openings, spark gap terminals adjustably mounted on the panel adjacent the corresponding sight openings, a rotary shaft in the frame below said terminals, cams fixed to said shaft in alignment with said terminals and Vconstituting movable spark gap terminals, spring contacts engaging the cams, leads ,connected to said spring contacts and provided with means at their free ends for connection with the spark plug circuits of corresponding4 engine cylinders, aground lead, two-way switches on the panel connected to the ground lead and adapted to connect one or the other of the corresponding spark gap terminals to said ground lead, and a motor for driving said shaft.

5. A testing device for internal combustion engines, comprising a casing, an insulating frame therein including a panel having a transparent section and a. series of sight openings therein, a mirror supported in angular relation adjacent said sight openings, spark gap terminals adjustably mounted on the panel adjacent the corresponding sight openv ings, a rotary shaft mounted in theframe below said terminals, cams fixed to said shaft in alignment with said adjustable terminals and constituting movable spark gap terminals, spring contacts engaging said cams, leads connected to said spring contacts and provided with means at their free ends for connection with the spark plug circuit of corresponding engine cylinders, a ground lead, two-way switches mounted on the panel connected to the ground lead and adapted to connect one or the other of the corresponding spark gap terminals to said ground lead, an electric motor, and reducing gearing connecting the motor to said shaft. v

6. A testing device for internal combustion engines, comprising a casing, an insulating frame therein including a panel having a transparent section and a series of sight openings therein, a mirror supported in angular relation adjacent said sight openings, spark gapterminals adjustably mounted on the panel adjacent the corresponding sight openings, a rotary shaft mounted in the frame below said terminals, cams fixed to saidshaft in alignment with said adjustable terminals and constituting movable spark gap terminals, spring contacts engaging said cams, leads connected to said spvring contacts and provided with means at their free ends for connection with the spark plug circuits of corresponding engine cylinders, a ground lead,`twoway switches mounted on the panel connected to the ground lead and adapted to connect one or the other of the corresponding spark gap terminals to said ground lead, an electric motor, reducing gearing connecting the motor tosaid shaft, and leads adapted to connect the motorto the source of ignition current for the engine.

7 A testing device for internal combustionl engines, comprising a casing, an insulating frame therein including a panel having a transparent section and a series of sight openings therein, a mirror supported in angular relation adjacent said sight openings, spark gap terminals adjustably mounted on the panel adjacent the corresponding sight openings, a rotary shaft mounted in the frame below said terminals, cams fixed to said shaft in alignment with said adjustable terminals and constituting movable spark gap terminals, spring contacts engaging said cams, leads connected to said spring contacts and provided with means at their free ends for connection with the spark plug circuits of corresponding engine cylinders, a ground lead, two-way switches mounted on the panel connected to the ground lead and adapted to connect one or the other of the corresponding spark gap terminals to said ground lead, an electric motor, reducing gearing connecting the motor to said shaft, and leads including an, adjustable rheostat adapted to connect the motor to the source of -ignition current for the engine.

8. A testing device for internal combustion engines, comprising a casing, an insulating frame therein including a panel having a transparent section and a series of sight openings therein, a mirror supported in angular relation adjacent said sight openings, spark gap terminals including screw spindles mounted in threaded openings in the panel adjacent the corresponding sight openings, a rotary shaft mounted in the frame below said terminals, cams fixed to said shaft in alignment with said spindles and constituting movable spark gap terminals, spring contacts engaging said cams, leads connected to said spring contacts and provided with means at their free ends for connection with the spark plug circuits of corresponding engine cylinders, a ground lead, two-way switches mounted on the panel connected to the ground lead and adapted to connect one or the other of the corresponding spark plug terminals to said ground lead, and a motor for driving said shaft.

9. A testing device for internal combustion engines, comprising a series of spark gaps each including a fixed terminal and a movable terminal, a motor driven shaft upon which the movable terminals are mounted to move past the corresponding fixed terminals, a separate lead from one terminal of each gap adapted tol be connected to the spark plug circuit of a corresponding engine cylinder, a ground lead, a switch to reach spark gap adapted to connect each to the ground lead or to connect the corresponding spark plug `lead to the ground, a, multiple point terminal onl said shaft, an adjustable terminal adjacent the same to establish spark gaps of varying widths, and means connecting said lastnamed terminals to the ignition coil and to the ground, respectively.

10. A testing device for internal combustion engines, comprising a series of spark gaps each including a fixed terminal and a movable'terminal, a rotary shaft upon which the movable terminals are mounted for periodic movement past the fixed terminals, and an electric motor for driving the shaft, a separate lead from one terminal of each gap adapted to be connected to the spark plug circuit'of a corresponding engine cylinder,

a ground lead, a two-way switch for each spark gap connected to the ground lead and adapted to connect one or the other terminal of the corresponding gap ,to ground, a multi` ple-point terminal on said shaft, an adjustable terminal adjacent the same to establish spark gaps of varying widths, and means connecting said last named terminals tothe ignition coil and to the ground respectively.

11. A testing device for internal combusv tion engines, comprising a series of spark gaps each including an adjustable fixed terminal and a movable terminal, a motor driven shaft u which the movable contacts are mounte to move past the corresponding fixed contacts, a separate lead from one contact of each gap adapted to be connected to the spark plug circuit of a corresponding engine cylinder, a groundlead, a switch for each spark gap adapted to connect each to thc ground lead or to connect the corresponding spark plug lead to the ground, a multiple point. terminal on said shaft, an adjustable terminal adjacent the same to establish spark gaps of varying widths, and-means connecting said last named terminals to the ignition coil and to the ground, respectively.

12. A testing device for internal combusresistance and an indicating device.

13. A testing device for internal combustion engines, comprising a series of spark gaps each including a tixed terminal and 'a movable terminal. a rotary shaft upon which the movable terminals are mounted for periodic movement past the fixed terminals, andan electric motor for driving the shaft, a separate rlead from one terminal of each gap adapted to be connected to the spark plug circuit ot' a corresponding engine cylinder, a ground lead, a two-way switch for each spark gap connected to the ground lead and adapted to connect one or the other terminal ot' the corresponding gap to ground, and a circuit from the timer to ground including an adjustable resistance and an indicating device.

14. A testing device for internal combustion engines, comprising a series of spark gapsv each including an adjustable fixed contact and a movable Contact, a motor driven shaft upon which the movable contacts are mounted to move past the corresponding fixed contacts, a separate lead from one contact of eachgap adapted to be connected to the spark plug circuit of a corresponding engine cylinder, a ground lead, a switch for each spark gap adapted to connect each to the ground lead or to connect the corresponding spark plug lead to the ground, and a circuit from the timer to ground including an adjustable resistance and an indicating device. l

15. A testing device for internal combustion engines, comprising a series of spark gaps each including a fixed terminal and a movable terminal, a motor driven shaft upon which the movable terminals are mounted to move past the corresponding fixed terminals,

a separate lead from Lone terminal of each gap adapted to be connected to the spark plug circuit of a corresponding engine cylinder, a ground lead, a switch for each spark gap adapted to connect each to the ground lead or to connect the corresponding spark plug lead to the ground, and a two branch circuit from the timer to ground, one branch including an adjustable resistance and a lamp, the other branch including an indicatori responsive to variations in speed of operation of the timer and to fluctuations in the speed thereof.

1G. A testing device for internal combustion engines, comprising a series of spark gaps each including a tixed terminaland a 30 movable terminal, a motor driven shaft upon which the movable terminals are mounted to move pastthe corresponding fixed terminals, a separate lead from one terminal of each gap adapted to be connected to the spark '95 plug circuit of a corresponding engine cylinder, a ground lead, a switch for each spark gap adapted to connect each to ,theground lead or to connect the corresponding spark plug lead to the ground, a twobranch circuit from the timer to ground, one branch including an adjustable resistance and a lamp, the other branch including an indicator responsive to variations in speed of operation of the timer and to fluctuations in the speed thereof, and a switch for alternately closing said branches.

17. A testing device for internal combustion engines, comprising a series ofl spark gaps each including an ladjustable fixed cony tact and a movable contact, a motor driven shaft upon which the movable contacts are mounted to move past the corresponding fixed contacts, a separate leadfrom one contact of each gap adapted to be connected to 105,1

the spark plug circuit of a corresponding engine cylinder, a ground lead, a switch for each spark gap. adapted to connect eachto the ground lead or to connect the corresponding spark plug lead to the ground, and a. two branch circuit from the timer to ground,

one branch including an adjustable resistance and a lamp, the other branch including an indicator responsive to variations in speed of operation of the timer and to iuctuations inthe speed thereof. y

18. A testing device for internal combustion engines, comprising a casing, an insulating frame therein including a panel having a( transparent section and two series of sight openings therein, a mirror supported in angular relation adjacent one series of said openings, spark gap terminals adjustably7 mounted on the panel adjacenty one series of sight openings, a rotary shaft mounted in the frame below said terminals, cams iXed to said shaft in alignment with said ad` justable terminals and constituting moving spark gap terminals, spring contacts engaging said cams, leads connected to said spring contacts and provided with means at their free ends for connection with the spark plug circuits of corresponding engine cylinders, a ground lead, two-Way switches mounted on the panel adjacent the second series of sight openings and connected to the ground lead and adapted to connect one or the other of the corresponding spark gap terminals to said ground lead, fixed sparking terminals between the ground and the leads aforesaid disposed below the corresponding sight openings, and a motor for driving said shaft.

19. A testing device for internal coinbustion engines, comprising a casing, an insulating frame therein including a panel having a transparent section and two series of sight openings. a mirror supported in angular relation adjacent one seiies of sight openings, spark gap terminals adjustably niount-ed on the panel adjacent said mirror, a rotary shaft mounted in the frame below said terminals, cams fixed to said shaft in alignment with said adjustable terminals and constituting movable spark gap terminals, spring contacts engaging the cams, leads connected to said spring contacts and provided With means at their free ends for connection with the spark plug circuits of corresponding engine cylinders, a ground lead, two-way switches mounted on the panel connected to the ground lead and adapted to connect one or the other of the corresponding spark gap terminals to said ground lead` fixed spark gap terminals interposed between the ground lead and the leads connected to said spring contacts and located below the corresponding sight openings of the second series, an electric motor, reducing gearing connecting the motor to said shaft, and leads adapted to connect the motor to the source of ignition vcircuit for the engine.

20. testing device for internal combustion envines com risinrr a series of s ark D n 7 l h l l gaps each including a plurality of relatively movable terminals, motor driven means for causing relative ,movement of said terminals to vary the gap between them, a separate lead from one terminal of each spark gap adapted to be connected to the spark plug circuit of a corresponding engine cylinder, a ground lead, and switch means for alternately connecting the corresponding spark gap or spark plug lead to the ground.

21. A testing device for internal combustion engines, comprising a series of spark gaps eachgincluding a fixed terminal and a movable terminal, means including a rotary shaft for moving said movable terminals with respect to the Vcorresponding fixed terminals, a separate lead from one terminal of each gap adapted to be connected to the spark plug circuit of a corresponding engine cylinder, a ground lead, and switch means for alternately connecting the corresponding spark gap or spark plug lead to the ground.

22. A testing device for internal combustion engines, comprising a series of spark gaps each including a fixed terminal andia movable terminal, means including a rotary shaft for moving said movable terminals with respect to said fixed terminals, a separate lead from one terminal of each gap adapted to be connectedto the spark plug circuit of a corresponding engine cylinder, a ground lead, switch means for alternately connecting the corresponding spark gap or spark plug lead, a multiple point terminal rotatable with said shaft, an adjustable terminal adjacent the same to establish spark gaps of varying Widths, and means connecting said multiple point and adjustable terminals to the ignition coil and to the ground respectively.

2". A testing device for internal combustion engines, comprising a series of spark gaps each including a fixed terminal and a movable terminal, means including a rotary shaft for moving said movable terminals with respect to said fixed terminals, a separate lead from one terminal of each gap adapted to be connected to the spark plug circuit of a corresponding'engine cylinder, a ground lead, switch means for alternately connecting the corresponding spark gap or spark plug lead, a multiple point terminal, a terminal adjacent thereto, one of said last named terminals being adjustable to establish spark gaps of varying Widths and one thereof being rotatable with said shaft, and means connecting said last mentioned terminals to the ignition coil and to the ground respectively.

In testimony whereof I affix my signature.

JOHN J. FERNANDEZ. 

